Experimental study on the water retention properties of the hard clay under cyclic suction conditions
CHEN Liufeng1，2，PENG Hua1
(1. School of Civil and Architectural Engineering，Wuhan University，Wuhan，Hubei 430072，China；2. College of Civil Engineering，Suzhou University of Science and Technology，Suzhou，Jiangsu 215011，China)
Abstract：In order to understand the unsaturated host medium of the high-level radioactive nuclear waste disposal repository in deep geological formation，a series of hydration and dehydration tests were performed on the hard clay which has been considered as the potential host medium for storage of the high-level nuclear waste. A suction control device was developed and the effects of suction cycles and suction gradients on the hard clay were investigated. The results showed that the suction gradient had little effect on the suction-water content relation，while the suction cycle has great effect on it，particularly the first cycle of hydration and dehydration. Nuclear magnetic resonance(NMR) method was used to study the water distribution during desaturation. The experimental results showed that the curves gave the evidence of the dependence of water content of the hard clay on the suction. The relationship between the water distribution and the pore size distribution was established. The water content variation during the hydration and dehydration depends on the state of adsorbed water.
陈留凤1，2，彭 华1. 干湿循环对硬黏土的土水特性影响规律研究[J]. 岩石力学与工程学报, 2016, 35(11): 2337-2344.
CHEN Liufeng1，2，PENG Hua1. Experimental study on the water retention properties of the hard clay under cyclic suction conditions. , 2016, 35(11): 2337-2344.
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2016, Vol. 35 
